The exercise is again simple (or if you want, much too simple): I take the OBR’s June 2010 forecast of output per hour, the observed data for total hours worked, and calculate a supply-side counterfactual path for real GDP. That path is compared against both the OBR’s June 2010 forecast of real GDP, and the actual data we have for for real GDP – I’ve rebased this time to highlight the difference since the pre-recession peak.

It remains true that a purely demand-side view of the UK recovery seems to prove too much. At least, it is hard to see that the weakness of RGDP relative to expectations circa June 2010 can be explained by a demand-side view; the shortfall in output is simply not a reflection of a shortfall in employment.

What happens next to productivity will define our economic performance over the next five years. In the end growing productivity is the key to our economic wellbeing. As the Nobel Laureate Paul Krugman once put it, productivity isn’t everything, but in the long run it is almost everything. Strong productivity growth will lead to higher earnings, higher living standards, and an easier job reducing the deficit. If productivity growth is weak, then we are in for some more tough years.

So why don’t we hear more about this from the politicians? Whatever they may say, they really can’t just legislate for higher earnings and lower prices. Those will come only as a result of a more productive and efficient economy.

It’s funny really. Some will attribute the stagnation of living standards since 2010 (or 2008) to mostly demand-side causes (e.g. Coalition austerity), and get extremely cross that politicians don’t take the AD policy seriously… and others get extremely cross that politicians don’t take supply-side policy seriously enough. The spectrum of views between the two extremes is also available.

I get more frustrated that we lack a common methodology or understanding of how to interpret the macro data. How do we decide the extent to which each view is true? Without that, I’m not sure why we should expect politicians and policymakers do much better than pick some position. (To be fair, many fail even that test.) Crazy models like the “paradox of toil” – which are taken seriously by some academics – make a mockery of the idea we can or even should separate the supply-side from the demand-side.

Unemployment towards the end of 2014 was 0.3% higher than in early 2007. Is it unreasonable based on figures like that, to say sure, the stagnation in UK living standards has been “clearly” supply-side? I could pick other data: low inflation or wage growth maybe, low (forecast) nominal GDP growth, and say, yes, demand-side problems remain.

But it’s complicated. If productivity growth has fallen to around 0% (god forbid) then nominal wage growth at around 2% is consistent with something like “full employment”. The argument goes back and forth… it only appears satisfying if you have strongly held prior beliefs and find a data point to confirm them.

Mr R. G. HAWTREY: In my view one of the most serious evils arising from fluctuations in the value of the currency is the trade. Whatever the causes of the trade cycle may be, one thing is common ground to every one, and that is that the trade cycle include the fluctuation of the price level combined with a fluctuation of productive activity. The two go together. Fall in price were due to increased production and the rise in scarcity, no further explanation would have to be looked for. But in fact the fall coincides with diminished production and the rise with increased production. The total value in money of the output of the world is increased both by the percentage by which prices rise and by the percentage by which the physical volume of production rises. Likewise, the subsequent fall in the price level is superimposed on the shrinkage of production. These wide fluctuations in money value of output are clearly a monetary phenomenon. A fall in the price level due to monetary causes brings about business depression and unemployment. The depression of the ’eighties, following the general adoption of the gold standard and the heavy fall in prices from 1873 onwards, supplies a well-known example.

More than eight decades later and it is now a minority view that the “wide fluctuations in the money value of output” … i.e. nominal GDP since 2008… are “clearly a monetary phenomenon”!

A mea culpa. I posted a chart of UK inflation expectations last month which showed no decline in gilt market-implied inflation expectations with the decline in the oil price. I was puzzled that published forecasts of expected inflation did not show the same decline as the market data. The reason is that my data was wrong. Sorry!

In fact I had posted the chart which was based on data for the forward measures of inflation, which comes from a different sheet in the Excel spreadsheet which the Bank publishes for the yield curve.

The correct chart for implied RPI inflation over the next 2.5 years is:

UK Market Inflation Expectations (2.5 Year). Source: BoE

By looking at the change in inflation expectations across different durations, we see that shorter-term inflation expectation have declined with the fall in the oil price:

UK Market Inflation Expectations (2.0, 2.5, 3.0 Year). Source: BoE

Here is the comparison with the forward measure which I used by mistake in the old post; the green line is expected inflation over the period from today to 2018, the blue line is expected inflation over 2018 to 2021.

It’s important to remember that the supposedly “orthodox” interpretation of the liquidity trap theory predicts that it was impossible for the Swiss National Bank to devalue the Swiss Franc in 2011. Monetary policy is all about interest rates, and when you have run out of interest rates, as the SNB had, there is nothing for your highly-paid central bankers to do. Perhaps they can meet up every now and then, and write a strongly-worded letter asking for fiscal stimulus if the expected path for inflation is a too low.

The Swiss National Bank shocked financial markets on Thursday by scrapping a three-year-old cap on the franc, sending the safe-haven currency soaring against the euro and stocks plunging amid fears for the export-reliant Swiss economy.

Only days ago, SNB officials had described the 1.20 francs per euro cap, introduced in 2011 at the height of the euro zone crisis to prevent the strong currency leading to deflation and a recession, as the cornerstone of the bank’s monetary policy.

The U-turn sent the franc nearly 30 percent higher against euro in chaotic early trading. It came a week before the European Central Bank is expected to unveil a massive bond-buying program that might have forced the SNB to intervene repeatedly to defend the cap.

We’ve also been told a few times that currency devaluation is zero-sum (since global aggregate demand is fixed), and so I presume the European economy will get a welcome boost from the devaluation of the Euro against the Franc. I suppose somebody, somewhere, is celebrating that the Swiss have stopped “sucking demand out of the world economy”?

Lars Svensson’s Foolproof Way has always seemed like the best option for the SNB to me.

This is also why looking at some measure of core inflation is important. If below target inflation is just due to lower oil prices, say, which in turn are just lower because of increased supply, say, [2] then this is no reason to think resources are being wasted. Just as inflation targeting central banks should largely see through any inflation caused by higher oil prices, they should also do the opposite. However in the UK, US and Eurozone core inflation is significantly below target, suggesting resources are being wasted everywhere.

I groaned all the way through Simon’s post. There is no official measure of “core inflation” in the UK, and the MPC rarely makes any reference to such an index. The ONS variant of the CPI which strips out energy, food, alcohol and tobacco is probably closest to what would be a textbook “core inflation” index. Here is the chart of that series:

As you can see, “core inflation” was above 2% all the way from 2010 through late 2013. I’ll predict the response: “Look at 2010 and 2011. Obviously we should strip out VAT too, you idiot!” OK, that’s sensible, I agree, but there is no ONS index which does that. The ONS produces literally hundreds of different price index series, and you want to argue that the one which really matters when setting monetary policy… doesn’t actually exist. Really?

Regardless, even with stripping out VAT in 2010/11, we are left with above-target “core inflation” in 2012 and and most of 2013. So, who was citing that data and arguing that we obviously had a too-expansionary monetary policy, and clearly there was little or no output gap with inflation pushed safely above target? I don’t remember Simon doing so. Yes, we can qualify the inflation data even further. Let’s strip out train fares, water prices, tuition fees, other administered prices, all prices which went up, etc. Those are (ahem, mostly) reasonable arguments. But recognize that this is basically the same logic followed by the hawks.

I could make a fence-sitting argument where I say the hawks might have been “correct” to take a demand-side view of high inflation in 2011, just as Simon might be “correct” to take a demand-side view of low inflation in 2015. But I don’t believe that. I think the hawks were mostly wrong before and I think Simon is mostly wrong now in taking a demand-side view of supply-side shocks. From my previous post, the recent downward revision to forecasts of inflation for 2015 happened at the same time as downward revisions to forecasts of unemployment. That is simply not what a negative demand-side shock looks like.

The “balance of risks” argument is reasonable, and it might be true that a slightly looser monetary policy will do little harm now – hey, after all, there is a risk house prices in London stopped going up*. In fact, sterling fell in response to the inflation data surprise, indicating precisely that money got slightly easier, so a “dovish” reaction to low inflation surprises is already embedded in current policy. In the long run I think we’ll have a more stable economy if monetary (and fiscal) policy makers can be encouraged into looking at “inflation” in a way which doesn’t require sharp swings in aggregate demand in response to supply shocks.

* This is a joke. Also it’s not a joke. Having UK monetary policy target the oil price with too high a weight would be likely to create excessive volatility in nominal demand and hence other nominal asset prices, so I think we’d expect to see more boom-bust housing cycles.